Exec a command for each git commit

Ever wanted to git bisect but not actually bisect? As in, you just want to run a command but on every commit.

Turns out, the answer is in git rebase. When rebasing interactively, you can append an “exec” command that will automatically execute in between each rebased commit.

pick 1111111 Refactor one thing
exec time make test
pick 2222222 Add new feature
exec time make test
pick 3333333 Refactor another thing
exec time make test

# Rebase 000000..333333 onto 000000 (3 command(s))
#
# Commands:
# p, pick = use commit
# r, reword = use commit, but edit the commit message
# e, edit = use commit, but stop for amending
# s, squash = use commit, but meld into previous commit
# f, fixup = like "squash", but discard this commit's log message
# x, exec = run command (the rest of the line) using shell
# d, drop = remove commit
#
# These lines can be re-ordered; they are executed from top to bottom.
#
# If you remove a line here THAT COMMIT WILL BE LOST.
#
# However, if you remove everything, the rebase will be aborted.
#
# Note that empty commits are commented out

In this illustrative example, we’ve decided to run time make test on each of our commits, to test for test performance regressions.

Neato!